com.github.yoojia.halo.utils.Scanner Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of halo-core Show documentation
A FAST && THIN && HIGH SCALABLE Java web framework
There is a newer version: 1.1.2
package com.github.yoojia.halo.utils;

import com.google.common.collect.Lists;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Method;
import java.net.URL;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.List;

/**
 * @author YOOJIA.CHEN ([email protected])
 */
public final class Scanner {

    private final Logger mLogger = LoggerFactory.getLogger(Scanner.class);

    private ArrayList mClasses;

    public enum ConsumeResult {
        CONSUMED, SKIP
    }

    public interface Visitor {
        ConsumeResult visit(String className) throws Exception;
    }

    public interface PrepareHandler {
        void prepare(String root, T module, Class hostType, Method method);
    }

    public void start(){
        mClasses = Lists.newArrayList();
        final long scanTime = System.nanoTime();
        final URL url = this.getClass().getResource("/");
        // 1. 当前项目下的类文件
        try {
            final Path base = Paths.get(url.toURI());
            mLogger.debug("Searching path: {}", base);
            final FileVisitor visitor = new SimpleFileVisitor() {
                @Override
                public FileVisitResult visitFile(Path path, BasicFileAttributes attr) throws IOException {
                    final Path clazz = base.relativize(path);
                    final String className = clazz.toString();
                    if (className.endsWith(".class")){
                        final String resolvedClassName = className.replace(".class", "").replace(File.separator, ".");
                        mClasses.add(resolvedClassName);
                    }
                    return FileVisitResult.CONTINUE;
                }
            };
            Files.walkFileTree(base, visitor);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        // 2. TODO 扫描 Jar 文件内的 class 文件
        SystemTime.log(scanTime, "Scan classes:" + mClasses.size());
    }

    public void walkClasses(Visitor visitor){
        if(mClasses == null) {
            throw new IllegalStateException("Cannot walk classes after scanner closed!");
        }
        final int max = mClasses.size() - 1;
        final List deleteRef = Lists.newArrayList();
        try{
            for (int i = 0;i <= max; ++i){
                final String item = mClasses.get(i);
                if (ConsumeResult.CONSUMED.equals(visitor.visit(item))){
                    deleteRef.add(item);
                }
            }
        }catch (Throwable e){
            throw new RuntimeException(e);
        }
        mClasses.removeAll(deleteRef);
    }

    public void clean(){
        mClasses.clear();
        mClasses = null;
    }

}